화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals, Vol.655, No.1, 142-149, 2017
Electrically active defects and related long-lasting persistent (photo-)conductivity phenomena in Thallium Bromide crystals
Several photoactive defects with optical activation energies of 0.55; 0.83, 1.1; 1.32 and 1.65 eV were revealed in TlBr. The trap level at 0.35 eV was identified by the thermally stimulated currents. The persistent conductivity effects were observed below 200 K, which could be initiated by the intrinsic light excitation. The strong superlinear dependence of the persistent conductivity on the applied electric field strength was observed. This effect could be explained by filling of the trapping states with the thermal activation energies of 0.08-0.12 eV. The pronounced enhanced photoconductivity could be thermally quenched above about 180 K, because of the emptying of the trapping states having activation energy of 0.63-0.65 eV.